Air pistol or rifle



Feb. 8, 1966 K. PARTANEN AIR PISTOL OR RIFLE Filed May 13, 1963 United States Patent 3,233,602 AIR PISTOL 0R RIFLE Kalevi Partanen, Puhurinpolku 1A, Tapiola, Finland Filed May 13, 1963, Ser. No. 280,047 4 Claims. (Cl. 124-15) bottom of the cylinder in which it functions. From this it follows that when the spring is released, its energy causes recoil and sidekick. Since the effect of the recoil depends very largely on the grip-power of the hand, which is difiicult to maintain constant, this recoil is detrimental to the accuracy of the pistol or rifle. This disadvantage has been eliminated in the present invention by using two pistons, one at either end of the spring. When the weapon is being loaded, the pistons are pressed inwards towards each other and connected together. To fire, therefore, it is only necessary to release the link between the two pistons, which entirely eliminates any inertia momentum. The pellet is expelled only by the compressed air generated by the piston nearest to the barrel. The other piston merely compresses air in an enclosed space. By carefully selecting the ratio between the lengths and weights of the two pistons, and the distances travelled by them, it is possible to arrange for their movement to end nearly simultaneously, and to make them create approximately equal pressures. This eliminates recoil while still ensuring that enough of the power produced by the spring is utilized.

The use of two pistons or of a piston and a weight is prior known in an air pistol or rifle. In these prior known constructions, however, the pistons are made to move inwards towards each other when released. Thus each piston requires its own spring. Consequently, the loading mechanism and, in general, the construction of the weapon is more complicated and expensive than it is in the air pistol or rifle according to this invention.

The accompanying drawing shows the mechanism of one embodiment of a recoilless air pistol or rifle according to this invention, in longitudinal section.

In addition to an actual firing piston 1, the mechanism includes a counter piston 2, and a spring 3 between the pistons.

A release device 4, 5, 6, 7, 8, 9, 10, 11 and 12 is fastened to piston 2 by means of screws 13. A trigger 14 is firmly attached to a firing cylinder 16 by its shaft and 'the length of a loading rod 17 is so determined that :the ratio between the distances a and b travelled by the pistons is equal to the ratio between the total weights of the pistons 1 and 2, said total weights comprising the weights of the pistons and of all the parts attached to them.

Upon release, the spring 3 presses the pistons 1 and 2 against both ends of the cylinder 16.

In loading, the rod 17 thrusts piston 1 towards piston 2 until the inside ends of the pistons touch each other. Simultaneously, piston 1 turns the spring 11 and the force of the spring thrusts part 9 in a clockwise direction so that the nose of part 5 is pressed into a recess in piston 1 and part 7 sticks to part 5 thanks to a spring 12. The weapon is then loaded.

To fire, part 7 is actuated by the trigger 14 until part 5 is able to turn. Then the force of the main spring 3 thrusts the end of part 5 out of the recess in piston 1, the angle of surface being by way of example 7.5 and the pistons 1 and 2 move off simultaneously. Since the ratio between the distances travelled by the pistons is inversely proportional to the weights of the pistons, and since the pistons are actuated by the same spring power, they both arrive at the opposite ends of the cylinder at approximately the same time. Furthermore, since the pressures in front of the two cylinders while they are moving are almost equal, the effect of the ail-stream behind the pellet and of the differences between the friction forces being insignificant, the result is a complete absence of recoil.

What I claim is:

1. An air gun, comprising a barrel adapted to receive a pellet, a cylinder connected to the barrel, passage means connecting a first end of the cylinder to the barrel, means closing the other, second end of the cylinder, opposed pistons reciprocable longitudinally within the cylinder adjacent the opposite ends thereof, and a common compression spring positioned between the opposed pistons and urging the pistons apart, means for loading the gun including means to move the pistons together in their loaded positions to place the spring in compression therebetween, means selectively to latch the pistons together in their loaded positions, and trigger means for releasing the latch to fire the gun, the pistons when thus released by the latch moving away from each other in the cylinder, and air compressed by the first piston during its firing travel flowing through the said passage into the barrel to expel the pellet therefrom.

2. An air powered firearm as in claim 1, said pistons having different lengths, Weights and distances of travel, the ratios between said lengths, said weights and said distances of travel being selected such that the movements of said pistons caused by the force of said spring end at substantially the same time.

3. An air gun as in claim 1, and wherein the second piston which lies nearer said second end of the cylinder, when unlatched from the other, first piston, is freely movable toward the second end of the cylinder but for the air which is compressed between the means closing the second end of the cylinder and the second piston.

4. An air gun as in claim 3, wherein the latching means comprises means providing a latching shoulder on one of said pistons, a detent pivotally attached to the other of said pistons for movement into and out of latching engagement with the shoulder, and means actuated by the trigger for thrusting the detent from engagement with the shoulder to fire the gun.

References Cited by the Examiner UNITED STATES PATENTS 2,495,460 l/1950 Koucky 42-l6 2,659,994 11/1953 Yale 89199 X 2,938,513 5/1960 Giss l24l5 FOREIGN PATENTS 376,259 3/ 1923 Germany.

RICHARD C. PINKHAM, Primary Examiner. W. R. BROWNE, Assistant Examiner. 

1. AN AIR GUN, COMPRISING A BARREL ADAPTED TO RECEIVE A PELLET, A CYLINDER CONNECTED TO THE BARREL, PASSAGE MEANS CONNECTING A FIRST END OF THE CYLINDER TO THE BARREL, MEANS CLOSING THE OTHER, SECOND END OF THE CYLINDER, OPPOSED PISTONS RECIPROCABLE LONGITUDINALLY WITHIN THE CYLINDER ADJACENT TO OPPOSITE ENDS THEREOF, AND A COMMON COMPRESSION SPRING POSITIONED BETWEEN THE OPPOSED PISTONS AND URGING THE PISTONS APART, MEANS FOR LOADING THE GUN INCLUDING MEANS TO MOVE THE PISTONS TOGETHER IN THEIR LOADED POSITIONS TO PLACE THE SPRING IN COMPRESSION THEREBETWEEN, MEANS SELECTIVELY TO LATCH THE PISTONS TOGETHER IN THEIR LOADED POSITIONS, AND TRIGGER MEANS FOR RELEASING THE LATCH TO FIRE THE GUN, THE PISTONS WHEN THUS RELEASED BY THE LATCH MOVING AWAY FROM EACH OTHER IN THE CYLINDER, AND AIR COMPRESSED BY THE FIRST PISTON DURING ITS FIRING TRAVEL FLOWING THROUGH THE SAID PASSAGE INTO THE BARREL TO EXPEL THE PELLET THEREFROM. 